There’s a hidden fact about northern Arizona that many non-residents don’t know. The landscape is littered with more than 600 volcanoes, many of which tourists drive right by without a passing glance, as they continue on their way to any of Arizona’s better known natural landmarks. The San Francisco volcanic field1 is more the 4,700 square km (1,800 square miles) in size, and contains volcanoes ranging in age from less than 1,000 years to over 6 million years old. Looking at it from above using Google’s terrain view, the sheer number of volcanoes popping up in one spot…